1. Field of the Invention
The present invention relates to lintels used in the construction industry to support masonry units. In particular, the present invention relates to repair of deflected lintels and installation of lintels that resist deflection.
2. Description of Related Art
Lintels support masonry over a door or window. They are typically made from 4xe2x80x3xc3x974xe2x80x3xc3x97{fraction (3/8)}xe2x80x3 angle iron, and can be up to twenty feet or more in length. Normally, each lintel is supported only by stands of masonry on either end of the lintel. However, with the rapid increase in construction in the United States, it has become the practice of some contractors to install 4xe2x80x3xc3x974xe2x80x3xc3x97{fraction (1/4)}xe2x80x3 or similar smaller-size masonry lintels with lag screws to adjoining headers, also referred to as beams or girders, over doors and windows. This practice may include supporting the lintel with posts during installation and while the masonry dries. When used in this fashion, the lintel and the lag bolts are subjected to fatigue stress and strain from thermal expansion due to temperature changes and the load of the carried masonry. Over time, the lintel deflects, or sags, and rotates, resulting in damage to the supporting veneer and an unsafe positioning of the masonry load, which must be repaired. These repairs are time consuming, labor intensive, and costly. These repairs can take up to three days to complete.
Common methods for repairing damaged lintels include: (a) having the owner continuously repair the masonry by pointing; or (b) removing the masonry and the damaged lintel, replacing the damaged lintel with a stiffer lintel, and replacing the masonry. Removal of the masonry usually results in irreparable damage to some or all of the masonry, such that the removed masonry must be replaced with new masonry. In such cases, the owner usually finds that it is very difficult to match the old masonry. Further, the irreparable masonry must be discarded in land fills, which adds additional cost to the repair project.
Typically, a failed lintel, or a lintel of inadequate strength, sags or deflects downward at the mid-section. Also, the exterior edge of the lintel may also rotate in a direction downward and away from the header. The 1997 Uniform Building Code, and the proposed International Building Code 2000, indicate that the limit of deflection for masonry is limited to L/600 or xe2x85x9cxe2x80x3, whichever is more critical.
There is a need for a lintel support brace for use in repairing damaged or sagging lintels, or that can be used as part of an original lintel installation.
It is an object of the present invention to provide a lintel support brace that can be used to repair damaged or sagging lintels and that can also be used as part of an original lintel installation.
It is another object of the present invention to provide a method of installing or repairing a lintel by providing a lintel support brace that transfers some or all of the load of the carried masonry to the header.
The above objects are achieved by providing a lintel support brace having a top portion, an opposing bottom portion adjustably coupled to the top portion, and a support arm coupled to the bottom portion, wherein the top portion and the bottom portion are configured to be attached to an adjoining header.
The present invention has significant advantages, including: (1) the removal and disposal of damaged masonry is not necessary, thereby preserving the aesthetic nature of the masonry and avoiding the time and expense associated with matching new masonry to the old masonry; (2) structural support for existing lintels is increased, thereby increasing the factor of safety against recurring damage; (3) the time and expense of repair projects is greatly reduced, for example, from 3 days to one half of one day; (4) the level of expertise required to perform the repair project is reduced, such that homeowners equipped with basic tools can perform the repair project; and (5) the present invention allows for normal thermal expansion of the masonry lintel, thereby preventing fatigue failure and residual stress due to boundary restraint conditions. In addition, by installing a plurality of lintel support braces according to the present invention, the span of the deflected beam is reduced and deflection is improved significantly. The placement of two lintel support braces reduces deflection significantly under the same loading conditions. Furthermore, the lintel support brace provides an additional factor of safety in deflection, provided the header has sufficient capacity to support the additional loading.
These objects and advantages, as well as others, will be evident from the following detailed description of the present invention.